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1.
Ping-Chi Hsu Jia-Ying Jhong Li-Ping Huang Kuo-Hsin Lee Hsin-Pao Chen Yue-Leon Guo 《International journal of molecular sciences》2021,22(8)
Di(2-ethylhexyl) phthalate (DEHP) is widely used as a plasticizer in the manufacture of polyvinylchloride plastics and has been associated with concerns regarding male reproductive toxicity. In this study, we hypothesized that maternal exposure to DEHP induces transgenerational inheritance of adult-onset adverse reproductive outcomes through the male germline in the F1, F2, and F3 generations of male offspring. Pregnant rats were treated with 5 or 500 mg of DEHP/kg/day through gavage from gestation day 0 to birth. The offspring body weight, anogenital distance (AGD), anogenital index (AGI), sperm count, motility, and DNA fragmentation index (DFI) were measured for all generations. Methyl-CpG binding domain sequencing was performed to analyze sperm DNA methylation status in the F3. DEHP exposure at 500 mg/kg affected AGD, AGI, sperm count, mean DFI, and %DFI in the F1; AGD, sperm count, and mean DFI in the F2; and AGD, AGI, mean DFI, and %DFI in the F3. DEHP exposure at 5 mg/kg affected AGD, AGI, sperm count, and %DFI in the F1; sperm count in the F2; and AGD and AGI in F3. Compared with the control group, 15 and 45 differentially hypermethylated genes were identified in the groups administered 5 mg/kg and 500 mg/kg DEHP, respectively. Moreover, 130 and 6 differentially hypomethylated genes were observed in the groups administered 5 mg/kg and 500 mg/kg DEHP. Overall, these results demonstrated that prenatal exposure to DEHP caused transgenerational epigenetic effects, which may explain the observed phenotypic changes in the male reproductive system. 相似文献
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目的 建立气相色谱-质谱法检测蔬菜中邻苯二甲酸二(2-乙基己基)酯(Di(2-ethylhexyl) phthalate, DEHP)、邻苯二甲酸二异丁酯(diisobutyl phthalate, DIBP)以及邻苯二甲酸二丁酯(dibutyl phthalate, DBP)3种主要塑化剂的含量。方法 样品经正己烷超声提取后, 经Ttx-5MS(30.0 m×0.25 mm×0.25 μm)色谱柱分离, 进样口温度为260 ℃; 载气流速为1.0 mL/min, 柱箱程序升温, 外标法定量检测。结果 在0.025~0.5 μg/mL浓度范围内3种塑化剂的线性关系良好(r>0.999), 检出限分别为0.0048、0.0080、0.015 μg/mL, 加标回收率为103.68%~118.65%, 相对标准偏差在1.16%~5.23%, 满足定量分析要求。结论 本方法简单, 快速, 适用于不同蔬菜中3种塑化剂的定量分析, 且部分塑化剂类化学污染物在叶菜类蔬菜中存在污染积累效应。 相似文献
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Bis(2-ethylhexyl) phthalate (DEHP) concentrations were measured at different stages in a full-scale sewage treatment plant (STP) and mass balances were calculated. The DEHP load to treatment process coming from the sewer system and the internal load comprising returned supernatants and filtrate from sludge treatment and excess secondary sludge were at the same level. The DEHP removal efficiency from the water phase at the STP was on average 94% of sewage DEHP, the main removal process being sorption to primary and secondary sludges. On average 29% of DEHP was calculated to be removed in the biological nitrifying-denitrifying activated sludge process, which was much less than expected from laboratory biodegradation studies described in literature. Monoethylhexyl phthalate, the primary biotransformation product of DEHP, was not detected at any treatment stage. Approximately 32% of DEHP in sewage was removed during anaerobic digestion of the sludge, while 32% remained in the digested and dewatered sludge. 相似文献
6.
我国对邻苯二甲酸酯类化合物检测方法的研究现状 总被引:1,自引:0,他引:1
邻苯二甲酸酯类作为塑料添加剂有80年的历史,很容易迁至食品和环境中,影响人类的身体健康。本文对邻苯二甲酸酯类化合物检测方法做了总结,为进一步认识邻苯二甲酸酯类化合物提供参考。 相似文献
7.
A Comparison of the Migration of ‘Spiked’ and ‘Intrinsic’ Substances from Paper and Board into Raisins and into Tenax as a Food Simulant 下载免费PDF全文
Four samples of paper and board (P/B) of a type used for packaging dry foods were subjected to migration experiments using raisins and the polymeric powder Tenax as a food simulant. The P/B samples contained only low levels of diisopropylnaphthalene (DiPN) and diisobutyl phthalate (DiBP), and so, experiments were also conducted after spiking the P/B with added model substances. These were o‐xylene, acetophenone, dodecane, benzophenone, DiPN and DiBP. Migration experiments into raisins and Tenax were conducted for 10 days at 40°C. Migration levels depended strongly on the nature of the substance. Migration from spiked P/B samples was more extensive (as a percentage of that available) than migration of intrinsic migratable substances, and so, studying spiked samples tends to be conservative. It is considered likely that this is because of binding of substances, especially aromatics with pi‐electrons such as DiPN and DiBP, to active sites on the surface of P/B fibres, resulting in non‐linear absorption isotherms. However, further work would be needed to prove this conclusively. Considering the results overall and also that raisins packed in P/B can have a shelf life of up to 1 year at ambient temperatures, the test results using Tenax as a food simulant are considered to be appropriate without application of a correction factor. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
8.
S M Dahiwale Chetan Bhongale S Roy P B Navle S N Asthana 《Journal of Energetic Materials》2019,37(1):98-109
Triple base propellant (TBP) containing mainly nitrocellulose, nitroglycerine, and nitroguanidine has been manufactured and coated with plasticizer in the present work. The aim was to study ballistics of di-butyl phthalate (DBP)-coated TBP. DBP solution in ethanol containing nitrocellulose dope was used for coating onto the propellant grains. DBP-deterred propellant showed inhibition to burning, resulting in lowering the values of ballistic parameters namely peak pressure (Pmax), dPmax, pressure index (α), and burning rate coefficient (β) during closed vessel firing. Increase in percentage of DBP in coating solution led to further decrease in ballistic parameters. Dynamic evaluation of the surface-moderated propellant showed comparatively lower muzzle velocity and chamber pressure for deterred propellant batches without leaving any unburnt particles in gun chamber at subzero temperatures with the lowest possible charge mass. The DBP-coated propellant can be useful in 155-mm artillery gun to achieve higher loading density as it has lower flame temperature and chamber pressure as compared to uncoated propellant which will result in increasing barrel life due to reduction in the barrel erosion. 相似文献
9.
采用含邻苯二甲酸二(2-乙基己基)酯(DEHP)的试验水样模拟城市取水水源发生DEHP水污染事故,测定粉末活性炭(PAC)对水样中DEHP的吸附性能,考察PAC炭种、吸附时间、DEHP初始浓度和PAC投加量等因素对DEHP的吸附量和脱除率的影响。试验结果表明:木屑PAC具有较大的比表面积,对DEHP具有良好的吸附效果,适用于DEHP水污染的应急处理。应急处理一般的DEHP水污染事故,DEHP污染浓度超标10~30倍时,PAC吸附DEHP的最佳条件为:吸附时间120 min,PAC投加量为20~80 mg/L,PAC对DEHP的吸附过程符合Henry等温式。 相似文献
10.
邻苯二甲酸酯类塑化剂是一类具有生殖毒性的环境激素类物质,通过违规添加或迁移而造成食品污染问题颇为严峻,开发适合现场的塑化剂快速监测方法非常重要。本研究以邻苯二甲酸二甲酯(DMP)为对象,建立了DMP的胶体金标记免疫层析检测试纸方法。采用柠檬酸三钠还原氯金酸制备了胶体金,将其标记DMP多克隆抗体,制备了金标抗体;采用棋盘法和单因素试验确定最佳包被浓度和二抗浓度分别为3000μg/mL和1600μg/mL,抗体浓度为稀释1.4倍,基于此建立了DMP免疫层析快速检测方法,其检测限为0.4μg/mL,5 min内肉眼可观察到检测结果,与其它结构功能类似物无明显交叉反应,特异性良好,白酒样品添加检测结果与GC-MS法相符。本法快速简单,稳定可靠,适用于实际样品中DMP的现场快速检测。 相似文献